When it rains it poors...

[SFXJ125]

On Friday jeep started acting funny in the morning with a slow start as well as a high idle when I parked it once arriving at work. Did it several times throughout weekend. She'd crank and crank and sometimes crank a little bit more and then finally turn over. Then once "warmed up" or driven a tad and shifted to park or neutral, rpms would jump to almost 2,000.

And then today at lunch, in the Jimmy John's drive thru (right after I ordered), the jeep died on me. I pushed it two car lengths to pick up my sandwich. Lol. Employee working the window gave me a funny look when I "pulled up", er I mean, "pushed up". Ate my sandwich in half embarrassment, half frustration and then the jeep hesitantly started up.

So, I took it straight home hoping and praying she wouldn't die on me again and she made it back. Got out OBD II scanner and came up with 0505, 0320, 0700 and 0743.

I then went to NAPA and bought CPS, and TPS (it was really busted...like broken and falling apart while still attached to TB) as well as ordered an IAC.

After replacing broke a$$ TPS and CPS tonight, the jeep cranks real fast and no indication of slow start. But, during and after test drive, noticed she still idles high in when shifting to neutral and park. Also idles higher than normal for my jeep. I'm used to seeing 650-700 rpm but I'm seeing 850-950 now.

Jeep shifts kinda hard once "warmed up". Not from 1 to overdrive but from drive into neutral or neutral to reverse or from reverse into park or park into reverse. I thought this was maybe due to high idle or is it a solenoid?

Checked codes after test drive and only getting 0700 and 0743 now. Haven't replaced the IAC but it's not throwing IAC code anymore so I don't know what to think. Dunno if its cause I disconnected the neg. battery cable before replacing CPS and the PCM reset itself or if replacing CPS and TPS actually made those other two codes go away.

So, do I replace IAC (cause it's acting like it needs to be replaced and the code reader threw IAC code earlier in the day)?

Also, any ideas about 0700 and 0743? My searching turns up solenoid testing and possibly replacing if bad. I believe I found a good write up on how to do that but if anyone else has some input, I'm all ears.

Jeep is 97 automatic that is not low on transmission fluid btw. And pours is spelled poors for a reason. Considering all the money I just threw at the jeep I found the joke rather fitting.

 

[YELLAHEEP]

....Jeep is 97.

Therein lies the problem in its totality.

Burn it with fire and start over.



:shhh:

 

[DutchVDub]

hit it with a hammer and claim hail damage

 

[Hypoid]

So, do I replace IAC (cause it's acting like it needs to be replaced and the code reader threw IAC code earlier in the day)?

Have you tried cleaning the IAC plunger and and the throttle body?

 

[SFXJ125]

Have you tried cleaning the IAC plunger and and the throttle body?

I tried that once before, I can't recall exactly what happened but I believe I ended up breaking it in the process. I'm almost positive part of my issue is the IAC or maybe a solenoid in trans. Or most likely, both...

Let y'all know how it turns out after cleaning tonight.

Also, forgot to mention that I tried fixing the "knocking" issue under the jeep yesterday as well. Removed, cleaned, loctited 4 x bolts on torque converter flex plate. Still knocking.... sounds like it's right there! Maybe bottom of oil pan. Aft most cylinder. IDK what to do. Ideas? Maybe the exhaust I'm about to drop in it will solve the issue.

 

[Buckshot62]

Check the flex plate.I had one with a cracked flex plate and it sounded like a rod knocking.

 

[SFXJ125]

Check the flex plate.I had one with a cracked flex plate and it sounded like a rod knocking.

Doh...I got it all back together and forgot to inspect for cracks...good call.

I imagine it would be pretty noticeable right? Any secret for inspecting and finding cracks?

I swear the sound is coming from torque converter flex plate.

 

[SFXJ125]

What if I start it up and then remove a plug wire one at a time? If the knocking stops when I remove a certain plug, will that tell me if it's rod knocking? Is this a bad idea? Better way for diagnosing?

It's been knocking for years btw. Finally got around to getting underneath and tightening flexplate bolts yesterday. None of the bolts were loose either.

 

[Buckshot62]

I had one that cracked almost all of the way around outside flex plate to crankshaft bolts. That one sped up and down with rpm's like a rod. Can't recall how I found it. (some timers is kicking in !) Was thinking I took a flashlight and shined between flex plate and torque converter.

 

[DutchVDub]

If you just had the transmission out I would double check you didn't have a flex plate bolt back out. That'll make for a good knocking sound too.

As for pulling a plug wire, I've down that to fine the weak/dead cylinder. Not sure how it would work for knocking.

 

[md21722]

NAPA sensors don't always work correctly. I use only genuine Mopar for the major engine sensors - crank, cam, TPS. A bad TPS will cause bizarre problems. Like speeding up to 3000 RPM when you start it or take your foot of the gas to coast.

 

[trippled]

Removing a wire could change the noise since it would reduce the cylinder pressure. You may or may not be able to see a crack in the flex plate unless you completely unbolt it from the crank.

 

[SFXJ125]

Haven't checked flexplate yet but have noticed that when I turn wheels ever so slightly the knocking sound gets louder which leads me to believe it's the exhaust. Taking plus off engine did nothing but shock my butt several times. LOL

After cleaning TB, the idling went back to normal...sort of. I noticed it was a little dirty and that the butterfly valve wasn't closing all the way. When I held the throttle cable with linkage by hand and closed butterfly all the way she was purring. I'm thinking I need to clean it more cause just a little bit of gap in valve causes a lot of high idling.

Once I driving the RPMs start to creep up little by little. I'm thinking it might not be the cleanliness of the TB but it's almost like the spring on the outside of the TB is worn which is not closing the butterfly completely. Or maybe it's a loose throttle cable? Any thoughts? New spring? Clean TB some more? Replace throttle cable assembly?

 

[trippled]

If you disconnect the cables will it go back all the way? I would suspect a bad cable or kickdown cable before a bad tb.

 

[SFXJ125]

If you disconnect the cables will it go back all the way? I would suspect a bad cable or kickdown cable before a bad tb.

I haven't conn cited all cables yet. Going to do that today. I have adjusted the kickdown cable. I believe it is the culprit. I don't know exactly how it works mechanically but I do know how to adjust it and I feel like it's not holding the butterfly valve closed enough. I feel like it should be tighter but what do I know? If I've adjusted it properly and I'm still getting a little higher than normal idle, is it most likely the cable?

 

[SFXJ125]

I disconnected cables and it seems as if the kickdown is not pulling the butterfly closed enough or the throttle is not pushing the butterfly closed enough. Anyone else run into this problem?

 

[SFXJ125]

It seems like the kickdown cable is either not tight enough (pulling butterfly valve closed at idle) or the throttle cable is not pushing it closed at idle. Anyone have experience with this issue.

 

[SFXJ125]

If you disconnect the cables will it go back all the way? I would suspect a bad cable or kickdown cable before a bad tb.

Alright brother... I disconnected them again this morning when I got to work and tried different combinations of cables hooked up and not hooked up. I'm about 99% sure it was my cruise control cable. I'll see how she drives at lunch and give you an update. Thinking I could just remove the cable since I never use it and was wondering if anyone has removed theirs?

 

[trippled]

The cables don't keep it closed. If removing them doesn't let the butterfly close, and you can physically push it closed to bring the idle to normal, then id suspect something wrong with the throttle body

 

[SFXJ125]

The cables don't keep it closed. If removing them doesn't let the butterfly close, and you can physically push it closed to bring the idle to normal, then id suspect something wrong with the throttle body

It was the cruise control cable all along. After removing and driving home I didn't have any idle issues upon start up or waiting at lights. The cable was too tight and not allowing the butterfly to close all the way. Thanks a lot for the help!:clap: